Patent GB-978208-A (GB)
Title: Improvements in and relating to automatic embossing machines
IPC: B41J3/413
Filed: 1963-08-23
Abstract: 978,208. Embossing machines. R. A. SCHACHT. Aug. 23, 1963 [Sept. 17, 1962], No. 33446/63. Heading B6F. Machines for embossing sheet metal, synthetic plastics; type-wheel machines; type-wheel actions; driving arrangements.-An embossing machine comprises a pair of type wheels 92, 94, Fig. 2, supported in spaced relationship on a stationary vertical shaft 110, the type wheels being provided with mating embossing character elements 114, a carriage 80 movable horizontally across the machine and a workpiece holder 82 mounted upon the carriage having means for advancing a workpiece 370 (Fig. 52, not shown) towards the type-wheels. In operation, on depression of a switch 516 the typewheels are set in continuous rotation by a motor 88, which through a gear-box 160, pulley wheel 108 and pulley belt 106, drives a two sleeve pulley block 102 drivingly connected to the type wheels. Following selection of a character and depression of a key 512 or 513 a solenoid 174 or 176, Fig. 3, is energized thereby releasing its spring-biased pawl 178 to engage with an appropriate ratchet tooth 172 to stop the type wheels in the selected position. Simultaneously with the depression of the key a solenoid 164 (Fig. 11, not shown) of an electromagnetically operated clutch 100 is energized and its associated yoke 165, Fig. 9, moves the upper clutch head 156 into engagement with the rotating lever clutch head 158 to rotate a shaft 150, whose cam lobe 146 displaces a cam rod 130. The cam rod 130 spreads apart a pair of cam blocks 136 causing the operation of upper and lower operating arms 122, 124, whose striking members 126, 128, respectively, displace the embossing elements 114 to emboss the workpiece 370. Paper, card, matrix sheet, feeding, clamping and guiding arrangements.-The workpiece 370 of sheet metal or synthetic plastic is retained in a workpiece holder 82, Fig. 1, between a jaw section 366 having a shoulder 368 extending around it. The workpiece is clamped in position by a spring-biased lock member 382 having a handle 384, Fig. 2. The workpiece holder 82 is supported on a retainer support 360 mounted on a rod 362, which is fixedly mounted on the carriage 80. Paper, matrix carriages and supports.-A carriage frame 80, Fig. 39, comprising a casting body 180 is supported for horizontal movement across the machine upon a carriage rail 78 by a pair of upper rollers 182, 184. Secure sliding engagement upon the rail is provided by a pair of front rollers 190, 192 and a pair of rear rollers 186, 188 to engage the front and rear of the guide rail, respectively. The carriage frame is also provided with a pair of legs 202, 204, depending downwardly the legs supporting a pair of flanged wheels to hug the bottom of the carriage rail. Alarms, margin and carriage stops.-A left side carriage stop member 194, Fig. 39, is provided which is adapted to abut against a stop 196 mounted on the carriage guide rail 78. Likewise, on the right-hand side a stop 196 is provided, which is adapted to contact the carriage return stop lever 200 positioned within a guide bracket 201. Letter-spacing mechanism; letter-spacing key actions.-A horizontal rack bar 210, Fig. 39, connected between the legs 204, 206 of the carriage frame 80 is provided with teeth 212, which co-operate with a pawl lever 214, having teeth 216 and 218. The lever 214 is pivotally connected to a pawl link 219, Fig. 51, which in turn is pivotally mounted on the carriage rail 78. The other end of the pawl lever 214 is attached to an operating arm 224 connected through an arm member 230 to the end of the lower character element operating arm 124, so that every time the arm 124 is actuated, when a character key is depressed, the feed pawl 214 is operated by an upward movement of the operating arm 224 and the carriage frame 80 is advanced one letter space. The movement of the carriage frame is effected by a tape 244, connected at one end to a stud 246 upon the leg 204 and is connected at the other end to a spring- biased reel 248 urging the carriage frame constantly to the left of the machine. When a space is required a spacer-bar 242, Fig. 1, is depressed energizing a solenoid 236 whose reciprocating armature 234 operates the pawl lever operating arm 224 in an upward direction through an arm 232 to which the arm 224 is fixed. Carriage-return mechanism; carriage releasing arrangements; carriage-return key actions.- On depression of a carriage-return key 310, Fig. 1, a solenoid 312, Fig. 34, attracts its vertically reciprocable armature 314 connected to one end of a clutch arm 316 to engage a friction clutch 322, mounted fixedly on a shaft 330 and driven from a pulley 302, with a tape reel 324, Fig. 39, whose one end is connected to the reel and the other end to an extension 328 depending from the leg 202 of the carriage frame. The friction clutch 322 transmits a torque from the shaft 330 to the tape reel to tension the tape and move the carriage frame from left to right. To prevent the carriage from overrunning a carriage stop member 198 engages a pivotally mounted contact rod 334 the lower end of which is connected to a striker arm 336, which is adapted to contact a spring-biased latch arm 338 having a shoulder 340 (Fig. 37, not shown) for latching of the clutch arm 316, so as to trip the latch arm 338 and lower the clutch arm 316 to disengage the friction clutch 322 from the tape reel 324. The carriage frame 80 can be released for free transverse movement along the rail 78 by means of buttons 252, 250 connected to a carriage disengaging rod 258, which is shaped to contact a disengaging pin 260 extending from the side of the pawl lever 214, to disengage the teeth 216, 218 from the rack 210. Line-spacing mechanism; line-spacing key actions.-For advancing the workpiece holder 82, Fig. 2, in a line spacing direction the carriage frame 80 is provided with a rack rod 400, Fig. 42, mounted at the bottom the carriage frame. The rack rod 400 has a rack blade 401 having a series of rack teeth 402 cooperating with a pair of pawls 404, 406 the latter being slightly longer than the former. A line spacing handle 408, biased by spring 409 is attached to one end of the rack rod 400. The workpiece holder is biased to move by a spring 414 connected at one end to a stud 416 on the holder 82 and at its other end to an anchor 418 on the carriage frame 80. When the handle 408 is depressed the rack blade 401 is pivoted out of engagement with the engaged pawl and the workpiece holder and the holder moves one half notch in the line spacing direction where it is engaged by the other pawl (Fig. 44, not shown). Automatic line spacing is effected on carriage return through a dog 420, fixed to the bottom of the line spacing rack rod 400, and which on contacting a stud 422 extending from the rear of the carriage rail 78 pivots the rack rod to advance the workpiece holder 82 one line space. Back-spacing mechanism; back-spacing key actions.-The back-spacing mechanism comprises a back-spacing key 262, Fig. 2, connected to an operating rod 264, which on depression of the key deflects an arm 266 of a pivoted rod 268 connected to a vertically movable operating member 274, Figs. 3 and 34, to move the member down whereupon its horizontal arm 278 contacts the free end of an upwardly biased pivot arm 280 to move it into the path of striking pins 300 on the pulley 302, driven continuously by a pulley belt 304 from the double sheave pulley 102. As a striking pin engages the pivot arm 280 it rotates the arm anti-clockwise, Fig. 3, and the rotation is transmitted to a spring-biased back spacing trigger 286, which extends through an opening of the carriage rail 78, Fig. 34, to engage a notch 292, Fig. 51, in a back spacing rod 294 mounted for sliding movement on the front of the carriage rail. The back spacing trigger 286 slides the back spacing rod 294 to the right whereupon its flanged end 296 which is provided with a tooth 298, engages the teeth 212 of the rack bar 210 on the carriage 80 to back space the carriage one tooth space. As the striking pin 300 rotates the arm anticlockwise, the arm 280 moves upwardly out of the path of the striking pins and the arm 280 is arrested by engaging the end of the operating arm 278 to prevent repeated back spacing. When the operating member 274 is subsequently raised vertically (by a cam not shown) the pivot arm 280 slides below the operating arm 278 under the influence of a spring 290 in readiness for subsequent operation. Multi-space back spacing is provided by a back spacing lever 346, Fig. 3, pivotally mounted at 348 and whose adjustment blade 350 can be moved into any one of three notches upon an adjustment 352. The lever is further provided with a cam surface 354 (Fig. 16, not shown), adapted to be contacted by the pivot arm 250 to limit its angular displacement. Erase-key actions.-An erase key 516 (not shown) may be operated in the same manner as the other keys 512 or 513 to select a pair of character elements having flat embossing ends so as to hammer out a previously embossed character. Keyboard arrangements; keys operating electric switch contacts.-The embossing machine is provided with a keyboard 76, Fig. 1, having a plurality of alpha-numerical keys, which in order to obtain a greater speed operation of the character wheel assembly 92 are divided into two groups of keys 512, 513 corresponding to the two ratchet solenoids 174 and 176, Fig. 3. The keyboard is also provided with an on-off switch 516, Fig. 56, which supplies current to the several circuits controlled by the keys 512 or 513. On closing of the switch 516 current flows through leads 520, 522 to a brush ring 504, swept by a brush 506 so that on depression of a key 512 the current is flowing through the brush and associated commutator segment 502, lead 518, associated switch 514 lead 523 and coil 530 of a relay 528 to close contacts 538, 542, 544. Contact 538 act as self-holding contact when k